Bump minitest from 6.0.4 to 6.0.6 in /docs

Bumps [minitest](https://github.com/minitest/minitest) from 6.0.4 to 6.0.6.
- [Changelog](https://github.com/minitest/minitest/blob/master/History.rdoc)
- [Commits](minitest/minitest@v6.0.4...v6.0.6)

---
updated-dependencies:
- dependency-name: minitest
  dependency-version: 6.0.6
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

docs/Gemfile.lock

@@ -157,7 +157,7 @@ GEM
     method_source (1.1.0)
     mini_mime (1.1.5)
     mini_portile2 (2.8.9)
-    minitest (6.0.4)
+    minitest (6.0.6)
       drb (~> 2.0)
       prism (~> 1.5)
     msgpack (1.8.0)

gem/ruby_ui.gemspec

@@ -20,5 +20,5 @@ Gem::Specification.new do |s|
   s.add_development_dependency "tailwind_merge", "~> 0.12"
   s.add_development_dependency "rake", "~> 13.0"
   s.add_development_dependency "standard", "~> 1.0"
-  s.add_development_dependency "minitest", "~> 5.0"
+  s.add_development_dependency "minitest", "~> 6.0"
 end